This invention relates to a tricycle, more particularly a tricycle having two fore wheels.
Since a tricycle has a better stability in low speed running or at standstill than a bicycle its demand has been increased in recent years. Among tricycles there are a first type having two rear wheels and one fore wheel and a second type having two fore wheels and one rear wheel. The former type is disclosed in U.S. Pat. No. 3,572,456, for example, and is advantageous in that its steering characteristic is excellent due to the fact that the load on the front wheel is small but disadvantageous in that the rear wheels may hit the rider's feet. To solve this problem it is necessary to take into consideration the arrangement of the wheels, load, the position of the center of gravity, the tire characteristic and their mutual relationships.
The second type is disclosed in U.S. Pat. Nos. 2,493,817 and 3,746,118, for example. Contrary to the first type, with this type the steering characteristic is inferior because of the large load on the fore wheels, but riding is easy as in an oridnary bicycle because of a single rear wheel.
The invention contemplates improvement of the tricycle of the second type while preserving the advantage of the first type. Recent requirements for the tricycle of the second type involves easiness of steering, capability of running along narrow roads, and occupation of small area while at standstill. To fullfil these requirements, efforts are now being made to develop a tricycle having a relatively small distance between two fore wheels. However, decrease in the wheel distance results in a great decrease in the running stability, one of the features of the tricycle of this type. Especially, the running stability is important at the time of running along a curve, and in an extreme case, the wheel closer to the center of the curve floats upwardly, thus causing tumbling down.